UNDERFOOT NOTES / Sheet 1 of ∞ / Scale 1:1 boots
Clear answers about the ground we walk on, from pebbles to plate boundaries.
surveyor: Writer, Big Questions
Lucinda writes brief pieces on very large ideas, like how long a mountain takes to wear away. She trims each article until only the useful parts are left. She's still learning, and she thanks every reader who writes in with a kind correction.
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24 May 2026 · 11 min
Earthquakes send out two kinds of waves: one pushes and pulls, the other shakes side to side. Only the first can cross a liquid, and that difference is how we learned the Earth has a liquid outer core.